The threat model of HEMET is similar to that of prior PPNNs [1]}, [2]}, [3]}, [4]}. Though an encryption scheme can be used to encrypt data sent to cloud, untrusted servers can make data leakage happen. HE enables a server to perform private inferences over encrypted data. A client sends encrypted data to a server performing encrypted inferences without decrypting the encrypted data or accessing the client's secret key. Only the client can decrypt the inference results using the secret key.
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